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Unread 29-03-2010, 13:45
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Re: How Do mecanum wheels handle the bumps?

Quote:
Originally Posted by Ether View Post
If the motor is providing a torque of 40 in-lbf to a wheel, and the wheel is not slipping, then the carpet MUST be reacting with a force of 10 pounds (for a 8" diameter wheel) in the plane of the wheel, acting against the wheel trying to push it forward.
Nope. The force is directed diagonally. An ideal mecanum roller can only apply force to the carpet in the direction parallel to the roller axis. Any component of force perpendicular to the roller axis acts to spin the roller instead.

Quote:
And yes, with the mecanum wheel there are additional vector forces at play. But they do not subtract from the 10 pounds. I encourage those of you who are using the "vector" argument to think a bit more about how the vectors are created.
The vectors don't subtract from the 10 pounds, but they do move it away from straight ahead.

Try your thought experiment with a single mecanum wheel. Better yet, try a real experiment with a single mecanum wheel, applying a spinning torque to it with your hand, and trying to hold it in place at the same time. You'll definitely find as much force pointing sideways as pointing forward.